HOORAY!! One World Trade Center Becomes NYC's Tallest Building!!

More than a decade after a terrorist attack brought down New York's twin towers, their under-construction replacement will become the city's tallest building on Monday.

The placement of a column of the 100th floor will bring the colossal new steel structure of One World Trade Center tower to a height of 1,271 feet – surpassing the frame of the Empire State Building, which is currently New York's tallest skyscraper, by 21 feet.

Built on what was referred to as ground zero in Lower Manhattan, the building is expected to reach 1,776 feet when it is finished by early 2014. The Willis Tower in Chicago, formerly known as the Sears Tower, is the country's current record holder at 1,450 feet.